-----Original Message----- From: ZHIZHIKIN Andrey [mailto:andrey.zhizhikin@leica-geosystems.com] Sent: 2021年3月3日 19:00 To: Bough Chen haibo.chen@nxp.com; Peng Fan peng.fan@nxp.com; u-boot@lists.denx.de; sbabic@denx.de Cc: dl-uboot-imx uboot-imx@nxp.com; tharvey@gateworks.com; festevam@gmail.com; Ye Li ye.li@nxp.com Subject: RE: [PATCH 2/2] mmc: fsl_esdhc_imx: remove redundant cmd11 related code.
-----Original Message----- From: haibo.chen@nxp.com haibo.chen@nxp.com Sent: Wednesday, March 3, 2021 10:06 AM To: peng.fan@nxp.com; u-boot@lists.denx.de; sbabic@denx.de Cc: haibo.chen@nxp.com; uboot-imx@nxp.com; tharvey@gateworks.com; ZHIZHIKIN Andrey andrey.zhizhikin@leica-geosystems.com; festevam@gmail.com; ye.li@nxp.com Subject: [PATCH 2/2] mmc: fsl_esdhc_imx: remove redundant cmd11 related code.
From: Haibo Chen haibo.chen@nxp.com
Common code already handle the voltage switch sequence based on spec, so remove the redundant voltage switch code.
Signed-off-by: Haibo Chen haibo.chen@nxp.com
drivers/mmc/fsl_esdhc_imx.c | 10 +--------- 1 file changed, 1 insertion(+), 9 deletions(-)
diff --git a/drivers/mmc/fsl_esdhc_imx.c b/drivers/mmc/fsl_esdhc_imx.c index af36558b3c..a199cf3df6 100644 --- a/drivers/mmc/fsl_esdhc_imx.c +++ b/drivers/mmc/fsl_esdhc_imx.c @@ -515,15 +515,6 @@ static int esdhc_send_cmd_common(struct fsl_esdhc_priv *priv, struct mmc *mmc, goto out; }
/* Switch voltage to 1.8V if CMD11 succeeded */if (cmd->cmdidx == SD_CMD_SWITCH_UHS18V) {esdhc_setbits32(®s->vendorspec,ESDHC_VENDORSPEC_VSELECT);
printf("Run CMD11 1.8V switch\n");/* Sleep for 5 ms - max time for card to switch to 1.8V */udelay(5000);}/* Workaround for ESDHC errata ENGcm03648 */ if (!data && (cmd->resp_type & MMC_RSP_BUSY)) { int timeout = 50000;@@ -839,6 +830,7 @@ static int esdhc_set_voltage(struct mmc *mmc) } #endif esdhc_setbits32(®s->vendorspec, ESDHC_VENDORSPEC_VSELECT);
mdelay(5);Why is this delay introduced here? It is not clear from the commit message whether and why it is required here.
If this is kept from the removed block - maybe it is better to move the corresponding comment here as well.
Hi Andrev,
Thanks for your careful review! Without this 5ms delay, with patch1 and remove the upper redundant cmd11 related code, mmc_switch_voltage() will fail, due to the second mmc_wait_dat0() return timeout. Seems for usdhc, gate off clock for 10ms is not enough. If total delay 15ms, then the second mmc_wait_dat0() can return normal. So I add 5ms delay here. Yes, I should add a comment for this 5ms in the code. You can also do the test on your side.
Best Regards Haibo
if (esdhc_read32(®s->vendorspec) &ESDHC_VENDORSPEC_VSELECT)
return 0;-- 2.17.1
-- andrey